JPH08323953A - Web offset printing - Google Patents

Abstract

PURPOSE: To stabilize the printing quality of a printing paper without slack of the paper by setting the diameter of blanket cylinders of a plurality of web offset printers getting larger successively along the moving direction of the printing paper passing through the blanket cylinders. CONSTITUTION: A web offset printer unit is constituted of first to fourth web offset printers 10, 12, 14 and 16, and a continuous printing paper 18 is so fed as to pass the cylinders 10, 12, 14 and 16. The printers 10, 12, 14 and 16 are provided respectively with a couple of blanket cylinders 10a, 10a'; 12a, 12'; 14a, 14'; 16a, 16a' and the printing paper is passed through between respective couples, and respective diameters of blanket cylinders are slightly increased successively along the moving direction of the printing paper 18. Therefore, slight tensile force is applied along the respective printers to generate no slack nor color shift of the printing paper 18 and stabilize the printing quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset rotary printing press having a plurality of offset rotary printing devices.

[0002]

2. Description of the Related Art In an offset rotary printing apparatus, a rubber called a blanket is interposed between the printing plates to transfer the ink onto the printing paper. This blanket is plate-shaped, and the blanket cylinder main body is generally provided with a tightening device for fixing the blanket. Further, between the blanket cylinder body and the blanket, paper or plastic film called under the blanket is sandwiched to adjust the printing pressure. There are various thicknesses under the blanket and blanket,
It is also common to change the thickness depending on the printing item or printing paper by making it the same for all offset rotary printing devices.

[0003]

However, in the conventional rotary offset printing press provided with a plurality of rotary offset printing devices, slack may occur in the print sheet due to the longitudinal extension of the print sheet. Therefore, the peripheral speed is increased in the cooling unit to pull the printing paper, but in each offset rotary printing device, the printing paper is sandwiched between the printing paper and the printing paper may not be pulled completely.
In addition, the amount of expansion of the printing paper may differ between colors, and in such a case, the slack of the printing paper was not eliminated even if the printing paper was pulled only by the cooling part.

The present invention has been made under the above circumstances, and an object of the present invention is to provide an offset provided with a plurality of offset rotary printing apparatuses capable of stabilizing print quality without causing slack of printing paper. It is to provide a rotary printing machine.

[0005]

In order to achieve the object of the present invention as described above, an offset rotary printing machine equipped with a plurality of offset rotary printing devices according to the present invention comprises a plurality of offset rotary printing devices. It is characterized in that the diameters of the plurality of blanket cylinders of the plurality of offset rotary presses are sequentially set to be large along the moving direction of the printing paper passing through the plurality of offset rotary printing devices.

[0006]

By setting the diameters of the blanket cylinders of the offset rotary printing apparatus to be successively larger along the moving direction of the printing paper passing through the offset rotary printing apparatuses, the blanket cylinders of one offset rotary printing apparatus can be made larger. It is possible to slightly increase the peripheral speed of the outer peripheral surface of the blanket cylinder in the next offset rotary printing device along the moving direction of the printing paper with respect to the peripheral speed of the outer peripheral surface. As a result, a slight pulling force is applied to the printing paper between one offset rotary printing device and the next offset rotary printing device, so that no slack occurs in the printing paper between the above and as a result. No color shift will occur.

The diameters of the plurality of blanket cylinders of the plurality of offset rotary printing apparatuses are set by sequentially setting the diameters of the plurality of blanket cylinder bodies of the plurality of blanket cylinders to be large along the moving direction of the printing paper. It is possible to set larger values in sequence along the moving direction of the printing paper.

The diameters of the blanket cylinders of the offset rotary printing apparatus can also be set by increasing the thicknesses of the blanket cylinders under the blankets sequentially along the moving direction of the printing paper. It is possible to set larger values in sequence along the moving direction of the printing paper.

The diameters of the plurality of blanket cylinders of the plurality of offset rotary printing devices may be further increased by sequentially increasing the thicknesses of the plurality of blanket cylinders of the plurality of blanket cylinders along the moving direction of the printing paper. Larger settings can be made in sequence along the paper movement direction.

The diameters of the plurality of blanket cylinders of the plurality of offset rotary printing devices are further set such that the diameters of the plurality of blanket cylinder bodies of the plurality of blanket cylinders are sequentially increased along the moving direction of the printing paper. The thickness of the blanket cylinder under the plurality of blankets is sequentially increased along the moving direction of the printing paper, or the thickness of the blankets of the plurality of blanket cylinders is sequentially increased along the moving direction of the printing paper. By setting at least any two of the setting, it is possible to set the values sequentially larger along the moving direction of the printing paper.

In the offset rotary printing apparatus in which the diameters of the plurality of blanket cylinders are sequentially set larger along the moving direction of the printing paper, the blanket cylinder main body of the plurality of blanket cylinders is a tightening device for attaching a plate-shaped blanket. Since a blanket is used and a plate-shaped blanket is used, the present invention can be easily implemented even in a conventionally commonly used offset rotary printing press.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. [First Embodiment] FIG. 1 is a schematic side view of only a main portion of an offset rotary printing machine provided with a plurality of offset rotary printing devices according to a first embodiment of the present invention.

The offset rotary printing press according to the first embodiment comprises four first to fourth offset rotary printing apparatuses 1.
It is equipped with 0, 12, 14, and 16. The first to fourth rotary offset printing devices 10, 12, 14, 16 are supplied with a long printing paper 18 pulled out from a winding paper in a paper feeding device (not shown), and the printing paper 18 is the first to fourth printing papers. 4 offset rotary printing device 10, 12, 14, 16
Is moved in the direction indicated by arrow A. During this time, the first to fourth offset rotary printing devices 1 are attached to the printing paper 18.
The respective predetermined images are printed from 0, 12, 14, 16 respectively.

In this embodiment, the first to fourth offset rotary printing devices 10, 12, 14, 16 are used to print images of mutually different colors on the printing paper 18, and the moving direction of the printing paper 18 is changed. The first to fourth offset rotary printing devices 10, 12, 14, 16 sequentially arranged along the line print black, cyan, magenta, and yellow images on the printing paper 18 in this order.

Further, in this embodiment, each of the first to fourth rotary offset printing devices 10, 12, 14, 16 prints on both sides of the printing paper 18, and therefore the printing paper 18 is used.
Has a substantially symmetrical structure above and below. Also, the first to the fourth
The respective structures of the offset rotary printing devices 10, 12, 14, 16 are the same as each other except for the dimensions.

The first offset rotary printing apparatus 10 includes a pair of blanket cylinders 10a and 10 'above and below a printing paper 18.
and a pair of blanket cylinders 10a, 10 '.
The sheet a holds the printing paper 18. Each of the pair of blanket cylinders 10a, 10'a has a pair of plate cylinders 10b, 1 '.
0'b is in contact. A pair of inking devices 10c, 10'c and a pair of dampening water devices 10d, 10'd are in contact with the pair of plate cylinders 10b, 10'b.

The second offset rotary printing device 12 also has a pair of blanket cylinders 12a and 12 'above and below the printing paper 18.
and a pair of blanket cylinders 12a, 12 '.
The sheet a holds the printing paper 18. A pair of plate cylinders (not shown) are in contact with each of the pair of blanket cylinders 12a and 12'a, and a pair of inking devices and a pair of dampening water devices are attached to these pair of plate cylinders. Are in contact.

The third offset rotary printing device 14 also has a pair of blanket cylinders 14a and 14 'above and below the printing paper 18.
and a pair of blanket cylinders 14a, 14 '.
The sheet a holds the printing paper 18. A pair of plate cylinders (not shown) are in contact with each of the pair of blanket cylinders 14a and 14'a, and a pair of inking devices and a pair of dampening water devices are attached to these pair of plate cylinders. Are in contact.

The fourth rotary offset printing device 16 also has a pair of blanket cylinders 16a and 16 'above and below the printing paper 18.
and a pair of blanket cylinders 16a, 16 '.
The sheet a holds the printing paper 18. A pair of plate cylinders (not shown) are in contact with each of the pair of blanket cylinders 16a and 16'a, and a pair of inking devices and a pair of dampening water devices are attached to these pair of plate cylinders. Are in contact.

In this embodiment, the blanket cylinders 10a, 10'a; 12a, 12 'of the first to fourth rotary offset printing devices 10, 12, 14, 16 are respectively provided.
The respective diameters of a; 14a, 14'a; 16a, 16'a are gradually and gradually increasing along the moving direction A of the printing paper 18.

When the size of the printing paper 18 is a B-size vertical half-cut and the pair of blanket cylinders 10a and 10'a of the first offset rotary printing device 10 are double-diameter blanket cylinders, respectively. Pair of blanket cylinders 10a, 10 '
The diameter of each of a is set to approximately 345 mm, and the pair of blanket cylinders 12a, 12'a; 14a, 1 of each of the second to fourth offset rotary printing devices 12, 14, 16 are provided.
4'a; 16a, 16'a; each has a diameter of about 345 m
It is increased by about 12.3 μm from m. That is, the first
Of the pair of blanket cylinders 10a, 10'a of the offset rotary printing apparatus 10 of FIG.
a and 12'a each have a diameter that is approximately 12.3 μm larger than the diameters of the pair of blanket cylinders 10a and 10'a of the first offset rotary printing device 10. The diameter of each of the 14 pairs of blanket cylinders 14a, 14'a is approximately 24.6 μm.
It is larger than the diameter of each of the pair of blanket cylinders 10a, 10'a of the first offset rotary printing device 10 by a fourth value.
Of each pair of blanket cylinders 16a, 16'a of the offset rotary printing apparatus 16 of FIG.
μm larger.

The blanket cylinders 10a, 10'a; 12a, 12'a; 14a, 1 in each of the first to fourth offset rotary printing devices 10, 12, 14, 16 are described.
4'a; 16a, 16'a are each rotated at the same angular velocity, so that a pair of blankets in any one of the first to third offset rotary printing devices 10, 12, 14 Body 10a, 10'a or 12a, 1
Second to fourth offset rotary printing devices 12, 14, which are located next to the peripheral speed of the outer peripheral surface of each of 2'a or 14a, 14'a along the moving direction A of the printing paper 18.
Blanket cylinder 12 in any one of 16
a, 12'a or 14a, 14'a or 16a, 1
The peripheral velocity of each outer peripheral surface of 6'a can be slightly increased. As a result, any one of the first to third offset rotary printing devices 10, 12, 14 and the second to fourth offset rotary printing devices 12, which are located next to the above, are provided.
Since a slight pulling force is applied to the printing paper 18 between the printing paper 18 and any one of the fourteenth and fourteenths, the printing paper 18 is not loosened during the above period, and as a result, the first to fourth Offset rotary printing device 10, 12, 14, 1
There is no occurrence of color misregistration in one multi-color printed image on the printing paper 18 after passing through 6.

Strictly speaking, blanket cylinders 10a, 10'a; 12a, 12'a in the first to fourth rotary offset printing devices 10, 12, 14, 16 respectively.
The diameters of 14a, 14'a; 16a, 16'a are
A slight color misregistration occurs because it is gradually but gradually increasing along the moving direction A of the printing paper 18, but this microcolor misregistration cannot be recognized by the ordinary human eyes.

First to fourth rotary offset printing apparatuses 1
Blanket cylinder 10a at 0, 12, 14, 16
10'a; 12a, 12'a; 14a, 14'a; 16
a, 16'a is, for example, a metal blanket body 2
0a, 20'a; 20b, 20'b; 20c, 20 '
c; 20d, 20'd, and the blanket cylinder main body 20a,
20'a; 20b, 20'b; 20c, 20'c; 20
d, 20'd, a blanket bottom 22a, 22'a; 22b, 2 made of, for example, paper wound around the outer peripheral surface to a uniform thickness
2'b; 22c, 22'c; 22d, 22'd and the lower blanket 22a, 22'a; 22b, 22'b; 22
A blanket 24a, 24'a; 24b, 24'b; 24c, 24 'made of, for example, rubber, is wound around the outer peripheral surface of c, 22'c;
c; 24d, 24'd.

In this embodiment, the blanket cylinder main bodies 20a, 20'a; 20b, 20'b; 20c, 2
0'c; 20d, 20'd diameter of printing paper 18
Of the blanket cylinders 10a, 10'a; 12a, 12'a in each of the first to fourth offset rotary printing devices 10, 12, 14, 16 as described above, by gradually increasing along the moving direction A. 14a, 1
4'a; 16a, 16'a diameter of printing paper 18
Along the direction of movement A of No.

In this experimental example, the plate cylinders 10b, 10'b; ... In each of the first to fourth offset rotary printing devices 10, 12, 14, 16 have the same diameter, Blanket cylinders 10a, 10'a; 12
a, 12'a; 14a, 14'a; 16a, 16'a, as long as they are rotated at an angular velocity twice as high as that of the a, 12'a; However, the blanket cylinders 10a, 10'a; 12 corresponding to the respective diameters of the plate cylinders 10b, 10'b;
Of course, it is also possible to gradually increase little by little along the moving direction A of the printing paper 18 in correspondence with the diameters of a, 12'a; 14a, 14'a; 16a, 16'a.

The first to fourth rotary offset printing devices 10, 12, 14 and 16 are used for the printing paper 1 as described above.
It goes without saying that the printing may not be performed on both sides of No. 8 and may be performed on only one side. In this case, the first to fourth rotary offset printing devices 10, 1
A pair of blanket cylinders 10a, 2, 14 and 16 respectively,
10'a or 12a, 12'a or 14a, 14 '
a or 16a, 16'a and the corresponding plate cylinder, inking device and dampening device, and instead of a pair of blanket cylinders 10a, 10'a or 12a, 12'a or 14a , 14'a or 1
Printing paper 18 in cooperation with either 6a or 16'a
An impression cylinder is used to hold the.

In this case, when the four impression cylinders (not shown) used in the first to fourth rotary offset printing apparatuses 10, 12, 14, 16 have the same diameter as each other, a corresponding pair of blankets. Body 10a, 10'a or 12
a, 12'a or 14a, 14'a or 16a, 1
Each rotation speed is set so that the outer peripheral surface rotates at the same peripheral speed as the peripheral speed of the other outer peripheral surface of 6'a, and the pair of blanket cylinders corresponding to the diameters of the above-described four impression cylinders (not shown). Either 10a, 10'a or 12a, 12'a or 14a, 14'a or 16a, 16'a is changed corresponding to the change in diameter. [Second Embodiment] FIG. 2 is a schematic side view of only a main part of an offset rotary printing machine provided with a plurality of offset rotary printing devices according to a second embodiment of the present invention.

The basic structure of the offset rotary printing press according to the second embodiment is the same as the basic structure of the offset rotary press according to the first embodiment described above with reference to FIG.
Structural members that are the same as the structural members of the first embodiment of FIG. 1 are given the same reference numerals and detailed description thereof is omitted.

The second embodiment is different from the first embodiment in that the blanket cylinder main bodies 20a, 20'a; 20 are different from each other.
b, 20'b; 20c, 20'c; 20d, 20'd respectively have the same diameter, instead of the blanket bottom 22
a, 22'a; 22b, 22'b; 22c, 22'c;
By gradually increasing the thicknesses of 22d and 22'd along the moving direction A of the printing paper 18, the first to fourth offset rotary printing devices 10, 12, 1 are set as described above.
Blanket cylinders 10a and 10 'in 4, 16 respectively
a; 12a, 12'a; 14a, 14'a; 16a, 1
That is, the respective diameters of 6'a are gradually and gradually increased along the moving direction A of the printing paper 18.

In the second embodiment having such a structure, the same effect as that of the first embodiment described above can be obtained, and similarly, the diameter of the corresponding plate cylinder or the impression cylinder in the case of single-sided printing can be obtained. The conditions in use of are also the same as those in the first embodiment described above. [Third Embodiment] FIG. 3 is a schematic side view of only a main part of an offset rotary printing machine having a plurality of offset rotary printing devices according to a third embodiment of the present invention.

The basic structure of the offset rotary printing press according to the third embodiment is the same as the basic structure of the offset rotary press according to the first embodiment described above with reference to FIG.
Structural members that are the same as the structural members of the first embodiment of FIG. 1 are given the same reference numerals and detailed description thereof is omitted.

The third embodiment differs from the first embodiment in that the blanket cylinder bodies 20a, 20'a; 20 are different from each other.
b, 20'b; 20c, 20'c; 20d, 20'd have the same diameter, respectively, instead of blanket 24
a, 24'a; 24b, 24'b; 24c, 24'c;
By gradually increasing the thicknesses of 24d and 24'd along the moving direction A of the printing paper 18, the first to fourth offset rotary printing devices 10, 12, 1 are set as described above.
Blanket cylinders 10a and 10 'in 4, 16 respectively
a; 12a, 12'a; 14a, 14'a; 16a, 1
That is, the respective diameters of 6'a are gradually and gradually increased along the moving direction A of the printing paper 18.

The third embodiment thus constructed can obtain the same effect as that of the first embodiment described above, and similarly, the diameter of the corresponding plate cylinder or the impression cylinder in the case of single-sided printing can be obtained. The conditions in use of are also the same as those in the first embodiment described above. [Fourth Embodiment] An offset rotary printing machine according to a fourth embodiment of the present invention, which is equipped with a plurality of offset rotary printing devices, is not shown, but the offset rotary printing according to the fourth embodiment is used. The basic structure of the printing press is the same as the basic structure of the offset rotary printing press according to the first embodiment described above with reference to FIG.

The difference between the fourth embodiment and the first embodiment is that the blanket cylinders 10a, 10 'in the first to fourth offset rotary printing devices 10, 12, 14, 16 are respectively different from each other as described above. a; 12a, 12'a; 14a,
14'a; 16a, 16'a diameter of printing paper 1
8 in order to gradually increase along the moving direction A of 8, the blanket cylinder main bodies 20a, 20'a; 20b, 20 '
b; 20c, 20'c; 20d, 20'd, respectively, the diameters of the blankets 22a, 22'a;
The thicknesses of 2'b; 22c, 22'c; 22d, 22'd are gradually increased little by little along the moving direction A of the printing paper 18, or blankets 24a, 24'a; 24b,
The thickness of 24'b; 24c, 24'c; 24d, 24'd is gradually increased little by little along the moving direction A of the printing paper 18, or at least two of them are combined.

The fourth embodiment thus constructed can obtain the same effects as those of the first embodiment described above, and similarly, the diameter of the corresponding plate cylinder or the impression cylinder in the case of single-sided printing can be obtained. The conditions in use of are also the same as those in the first embodiment described above.

The above-mentioned embodiment mentioned here is the case of an offset rotary printing machine of the type using dampening water.
Needless to say, the present invention can also be applied to an offset rotary printing machine of the type that does not use fountain solution.

[0038]

As described in detail above, an offset rotary printing machine provided with a plurality of offset rotary printing devices according to the present invention does not cause sagging of printing paper and does not cause color misregistration. It is possible to stabilize the quality.

[0039]

[Brief description of drawings]

FIG. 1 is a schematic side view of only a main part of an offset rotary printing machine including a plurality of offset rotary printing devices according to a first embodiment of the present invention.

FIG. 2 is a schematic side view of only a main part of an offset rotary printing machine including a plurality of offset rotary printing devices according to a second embodiment of the present invention.

FIG. 3 is a schematic side view of only a main part of an offset rotary printing press including a plurality of offset rotary printing devices according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... 1st offset rotary printing apparatus 12 ... 2nd offset rotary printing apparatus 14 ... 3rd offset rotary printing apparatus 16 ... 4th offset rotary printing apparatus 18 ... Printing paper 10a, 10'a ... Blanket cylinder
10b, 10'b ... plate cylinder 10c, 10'c ... inking device 10d, 10'd ... dampening water device 12a, 1
2'a ... blanket cylinder 14a, 14'a ... blanket cylinder 16a, 16'a ... blanket cylinder 20a,
20'a; 20b, 20'b; 20c, 20'c; 20
d, 20'd ... Blanket body 22a, 22 '
a; 22b, 22'b; 22c, 22'c; 22d, 2
2'd ... under the blanket 24a, 24'a; 24b,
24'b; 24c, 24'c; 24d, 24'd ... Blanket.

Claims (6)

[Claims] 1. A plurality of offset rotary printing devices are provided, and the diameters of the plurality of blanket cylinders of the plurality of offset rotary printing devices are sequentially set to be large along the moving direction of the printing paper passing through the plurality of offset rotary printing devices. An offset rotary printing press characterized by the following. 2. The diameter of a plurality of blanket cylinders of a plurality of offset rotary printing devices, and the diameter of a plurality of blanket cylinder bodies of the plurality of blanket cylinders are sequentially set to be large along the moving direction of the printing paper, whereby 2. The rotary offset printing press according to claim 1, wherein the offset rotary printing press is set to be larger sequentially along the moving direction of the printing paper. 3. The diameters of the plurality of blanket cylinders of the plurality of offset rotary printing devices are set so that the thicknesses of the plurality of blanket cylinders under the plurality of blanket cylinders are sequentially increased along the moving direction of the printing paper. 2. The rotary offset printing press according to claim 1, wherein the offset rotary printing press is set to be larger sequentially along the moving direction of the printing paper. 4. The printing is performed by sequentially setting the diameters of the plurality of blanket cylinders of the plurality of offset rotary printing devices such that the thicknesses of the plurality of blanket cylinders of the plurality of blanket cylinders are sequentially increased along the moving direction of the printing paper. The rotary offset printing press according to claim 1, wherein the offset rotary printing press is set to be larger in sequence along the moving direction of the paper. 5. The diameters of a plurality of blanket cylinders of a plurality of offset rotary printing devices, and the diameters of cylinder bodies of the plurality of blanket cylinders of the plurality of blanket cylinders are sequentially set to be large along the moving direction of the printing paper. The thickness of the plurality of blanket cylinders under the plurality of blankets may be sequentially set to be larger along the moving direction of the printing paper, or the thickness of the plurality of blankets of the plurality of blanket cylinders may be sequentially set along the moving direction of the printing paper. 2. The offset rotary printing press according to claim 1, wherein the offset is set to a large value sequentially along the moving direction of the printing paper by combining at least any two of the large settings. 6. The blanket cylinder main body of the plurality of blanket cylinders is provided with a tightening device for attaching a plate-shaped blanket, and the blanket is a plate-shaped one. Item 6. An offset rotary printing press according to any one of items 5.